1. Field of the Invention
The invention is related to subsurface safety valves useful in wells. More particularly, the invention relates to a mechanism for either the permanent or temporary locking open of the closure device in a tubing retrievable subsurface safety valve.
2. Prior Art
In the oil and gas industry it is accepted practice to use safety valves positioned within the well tubing for regulating the flow of well fluids from the producing formation to the surface of the well. This is a critical safety feature in the event there is some emergency situation in the well or at the surface of the well requiring termination of well fluid flow. Safety valves are placed in the well by either using setting methods to install well bore mounted safety valves or by connecting a safety valve in the tubing string itself. The latter are referred to as tubing retrievable subsurface safety valves.
It is often necessary to "lock" open the closure device which is in the safety valve. In the event the safety valve is malfunctioning it will be necessary to install a secondary safety valve, by either wireline or through the flow line techniques. It is not always necessary to permanently lock open the valve closure device. There are times when it is desired to only temporarily lock open the closure device and later be able to place the safety valve in operation.
It is an object of the present invention to provide a subsurface safety valve capable of being temporarily or permanently locked in the open to flow position.
A further object is to provide a tubing retrievable subsurface safety valve capable of being either temporarily or permanently locked in the open to flow position.
Another object of the invention is to provide a tubing retrievable subsurface safety valve capable of being either temporarily or permanently locked in the open to flow position using either wireline or through the flow line techniques.
The above and other objects and features of the invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred embodiment of the invention is shown.